Automotive fuel system seals include polymeric, deformable components that are widely used in many different applications to make a pressure-tight joint between parts, and typically include ring-shaped axial seals and radial seals or O-rings. In use, radial seals are compressed in a radial direction perpendicular to a seal centerline on radially inside and outside surfaces of the radial seal's cross-section, whereas axial seals are compressed in an axial direction parallel to a seal centerline on axially opposed surfaces of the axial seal's cross-section.
Axial seals are widely used to seal openings of containers. For example, axial seals are often used to seal an opening in a fuel tank and can be disposed in a flange-type joint between a mounting flange of a fuel delivery module and an outer surface of a fuel tank.